Ten inches in thickness will support 250 pounds per square foot of surface. It is usual to estimate that ice eighteen inches thick will support a railway train. WEIGHT OF ICE.--One cubic foot of ordinary ice will, on the average, weigh fifty-seven and one-quarter pounds, while a cubic foot of water weighs sixty-two and one-half pounds. Thirty-six cubic feet of ice weigh 2,000 pounds. But as stored in the house, it is reckoned that forty-two to fifty cubic feet of space is required per ton of ice, depending upon the thickness of the ice and the care with which it has been cut and stored. CHAPTER VI. THE USE OF ICE IN REFRIGERATION. Cold Storage Ice Houses--Their Value for Handling Meats, Fruits and Vegetables--What They Will Do--Principles of Construction and Operation--How to Build Them--The Dairy and Cold Storage Houses--Convenience and Economy of Combining Them--Combined Ice House and Dairy--Very Cheap Ice Houses--How to Cut Ice in Small Quantities--Co-operation among Farmers to Secure Advantages of Ice Supplies. THE USES OF REFRIGERATION are numerous in these days of invention and economy. The health, comfort and convenience of the civilized world are so intimately interwoven with results directly dependent upon the command, at will, of low temperature, that it is now of paramount importance to everyone. Refrigeration in the commercial world is largely secured by mechanical means, and this method will receive notice in a later chapter. Cold storage, secured by ice, is in use all over this country, for domestic and trade purposes in preserving food products. The benefits of cold storage could be much more widely diffused, than at present, throughout all the farming communities, where ice forms naturally during the winter, adding materially to their profits and convenience, and an attempt is here made to show, in a practical way, how it can be secured. THE CONSTRUCTION of a cold storage ice house, and the tools and methods employed for cutting and housing the ice, as well as the benefits to be secured, will be considered. Only such facts as have stood the test of practical experience, and which are within the limits usually attained by those who have good cold storage in use from year to year, will be presented. These results are only attainable by properly constructed storage houses, sufficient supply of ice, correct condition of articles when placed in cool room, length of time they are kept there and cleanliness. Cold storage houses, not built on correct principles, or improperly used, will prove of little account, and disappointment will follow their use. [Illustration: FIG. 61. A SIMPLE DELIVERY ICE WAGON.] Cold storage may be used to advantage in prolonging the market for many products. The entire crop, of fruit in particular, need not be shipped at once, but by proper picking and storing shipping can be extended over several months.